IV. Spaceflight

This is the final part of "From Stargazers to Starships," a historical overview of spaceflight, stressing the technology of rockets, satellites and orbits, and its use in unmanned missions.

It consists of four main parts:

The principles of rocketry and its evolution, from early Chinese rockets to Robert Goddard's work (especially the adaptation of the DeLaval nozzle), to rocket development in WW II and to the "space race" after the launch of Sputnik 1.

The many different uses of unmanned spacecraft, with examples and links.

Some orbits and orbital maneuvers of special significance--synchronous and sun-synchronous orbits, Lagrangian points and gravity-assist maneuvers, by which a spacecraft deflected my a moving planet can gain or lose velocity. That last item has an interesting connection to the water turbine designed by Lester Pelton in California, shortly after the Gold Rush.